wycks

Will add a little “x” next to any files/folders set to 777, since this is inherently insecure. Checks all recursive folders that come with a default WordPress install.
This plugin can be CPU intensive as it iterates over your whole folder/file structure to gather statistics.
Notes :
<ul>
<li>Checks root, wp-admin, wp-content, wp-includes and all sub folders</li>
<li>Includes your plugin and theme folders</li>
<li>Ignores images, text, CSS , and translation files</li>
<li>Will exclude the cache folders since they contain to many files to scan.</li>
<li>Requires PHP 5.1.2 or greater</li>
<li>Please run this during low traffic.</li>
</ul>
This plugin will not return accurate results under IIS or WAMP stack due to how windows handles file permissions.

File Permissions & Size Check

Simple plugin that checks your WordPress install and shows your file permissions, size, and last modified date.

Jason Tucker

This plugin will display the images defined using add_image_size in function.php and from installed plugins. Values are displayed in the Media Settings screen. 
You can see how images are https://codex.wordpress.org/Function_Reference/add_image_size
This plugin is based on the plugin: “Image sizes in admin dashboard!” by mansoormunib

Display Registered Image Dimensions

This plugin will display the images defined using add_image_size in function.php and from installed plugins. Values are displayed in the Media Setting …

File Permissions & Size Check vs Display Registered Image Dimensions